Oprah Winfrey will reportedly play the lead role in HBO Film’s The Immortal Life of Henrietta Lacks.

Oprah Winfrey’s New Role

While it’s a rare occurrence for Winfrey to act, Henrietta Lacks’ story has become a major focus for the media mogul. The passion project started back in 2010, when Winfrey signed on as an executive producer for the adaptation of Rebecca Skloot‘s nonfiction bestseller of the same name alongside Alan Ball (True Blood, Six Feet Under). Winfrey has only recently committed to playing Lacks, according to Deadline.

The Immortal Life of Henrietta Lacks tells the story of the eponymous African American woman whose cervical cancer cells were used without authorization to create the first immortal human cell line. The cell line, named HeLa, was created back in 1951 and went on lead to numerous breakthroughs in medicine.

The movie tells Lacks’ story through the eyes of her daughter Deborah Lacks, who Winfrey will be portraying.

Winfrey is best known for hosting The Oprah Winfrey show from 1986 until her retirement in 2011. Throughout her career, she’s occasionally dabbled in acting, making her big screen debut in 1985 in The Color Purple as Sofia. More recently, she’s had scene-stealing roles in Lee Daniel’s The Butler and in Selma. Winfrey is also slated to star in Richard Pryor: Is It Something I Said? and in TV series Queen Sugar, which she co-created with Ava DuVernay.